1<html lang="en"> 2<head> 3<title>Stdarg - Untitled</title> 4<meta http-equiv="Content-Type" content="text/html"> 5<meta name="description" content="Untitled"> 6<meta name="generator" content="makeinfo 4.13"> 7<link title="Top" rel="start" href="index.html#Top"> 8<link rel="up" href="Arglists.html#Arglists" title="Arglists"> 9<link rel="next" href="Varargs.html#Varargs" title="Varargs"> 10<link href="http://www.gnu.org/software/texinfo/" rel="generator-home" title="Texinfo Homepage"> 11<meta http-equiv="Content-Style-Type" content="text/css"> 12<style type="text/css"><!-- 13 pre.display { font-family:inherit } 14 pre.format { font-family:inherit } 15 pre.smalldisplay { font-family:inherit; font-size:smaller } 16 pre.smallformat { font-family:inherit; font-size:smaller } 17 pre.smallexample { font-size:smaller } 18 pre.smalllisp { font-size:smaller } 19 span.sc { font-variant:small-caps } 20 span.roman { font-family:serif; font-weight:normal; } 21 span.sansserif { font-family:sans-serif; font-weight:normal; } 22--></style> 23<link rel="stylesheet" type="text/css" href="../cs.css"> 24</head> 25<body> 26<div class="node"> 27<a name="Stdarg"></a> 28<p> 29Next: <a rel="next" accesskey="n" href="Varargs.html#Varargs">Varargs</a>, 30Up: <a rel="up" accesskey="u" href="Arglists.html#Arglists">Arglists</a> 31<hr> 32</div> 33 34<h3 class="section">13.1 ANSI-standard macros, <samp><span class="file">stdarg.h</span></samp></h3> 35 36<p>In ANSI C, a function has a variable number of arguments when its 37parameter list ends in an ellipsis (<code>...</code>). The parameter list 38must also include at least one explicitly named argument; that argument 39is used to initialize the variable list data structure. 40 41 <p>ANSI C defines three macros (<code>va_start</code>, <code>va_arg</code>, and 42<code>va_end</code>) to operate on variable argument lists. <samp><span class="file">stdarg.h</span></samp> 43also defines a special type to represent variable argument lists: this 44type is called <code>va_list</code>. 45 46<ul class="menu"> 47<li><a accesskey="1" href="va_005fstart.html#va_005fstart">va_start</a> 48<li><a accesskey="2" href="va_005farg.html#va_005farg">va_arg</a> 49<li><a accesskey="3" href="va_005fend.html#va_005fend">va_end</a> 50</ul> 51 52 </body></html> 53 54